1. Field of the Invention
This invention is a method and an apparatus for maintaining an opening in outdoor ice, particularily during winter on lakes and rivers. The method and apparatus are specifically intended to be utilized in conjunction with ice fishing.
2. The Prior Art
There are several existing methods and devices for keeping a fishing hole open through ice in winter. In ice fishing, the fisherman (inclusive of men, women and children) first makes a hole in the ice. The hole can be made with a manual auger, a power auger, a chisel, or even a chainsaw. The most commonly used technique and tool is the manual auger which makes a perfectly round hole with a diameter which is typically 6, 7 or 8 inches of constant cross section. The technique and tool which requires the least effort is the power auger which typically makes a similar or larger perfectly round hole. The manual auger can be carried anywhere; the power auger usually has to be carried on and supported by a vehicle. The impact ice chisel requires the most effort, and makes a hole of errotic size and cross section. A hole cut by a chainsaw is usually square.
The most popular technique and device is the manual auger, either of a helical screw type or of the "Swedish" type with a spoon shaped cutter. These devices are the least costly, are easy to carry, require less effort than an impact chisel, and makes a nice clean hole through ice of any thinkness. A shaft extender can be used on manual augers and they can quite effectively go through 48 inches of ice.
By virtue of the popularity of the manual auger, the most frequently encountered and utilized fishing hole is a perfect diameter, in the range of 6 to 8 inches in diameter.
Fishermen repeatedly use the same location, be it in the open out on the ice, or in a fish house. They go out, open the hole and go fishing. At the end of the day they leave and may not return for a day, several days or a week. Each time they return they have to re-open the hole. The work is dispised and is considered a necessary evil. There are several devices used to keep fish holes open for short periods of time. The most common is a tapered pail inserted down into the hole and left there to freeze in. When the fisherman returns, the pail is popped out of the hole. Some of these pail devices have heaters. There are several problems with pails. They only work for a relatively short period of time, i.e. overnight. They must be ballasted with removable dry ballast because of natural buoyancy. They break. They freeze in and cannot be removed. They are only available in large diameters, i.e. ice cream and 5 gallon pails, they only work for short depths of up to 18 inches. Ice freezes under the bucket and sill requires some reopening effort.
There is a definite need and want for a method and an apparatus to keep fishing holes open for extended periods of time and through any normally encountered thickness of ice.